Method and device for cleaning guide rollers in a web-fed rotary press

ABSTRACT

Guide rollers in a web-fed rotary printing press are cleaned by a web of material that is provided with signal information, such as a bar code or a punch code. The retrievable signal information is used by one or more signal reading devices that are used to apply cleaning agent to the web and to create a speed differential between the guide roller and the material web.

This is a national stage application of PCT/DE98/01383 filed May 20,1998.

FIELD OF THE INVENTION

The present invention relates to a method and to a device for cleaningguide rollers in a web-fed rotary printing press. A web of material thatcarries a cleaning agent is provided with coded information. The codedinformation is detected by a sensor and is used for controlling thecleaning of the guide rollers.

DESCRIPTION OF THE PRIOR ART

A device for cleaning paper guide rollers of a web-fed rotary printingpress is known from DE 37 14 143 C2. In this device, a running paperweb, which is not being printed upon, is temporarily wetted with acleaning fluid, which cleaning fluid is then transferred to the paperguide rollers and thereafter is removed, together with any ink remnantsremoved from the paper guide rollers, by a following portion of thepaper web which is not wetted with the solvent. The, paper web has aspeed from that of the circumferential speed of the paper guide roller.This difference in speed different is generated by means of drive motorsacting on the paper guide roller.

DE 44 27 816 A1 describes a method for the cleaning of cylinders of asheet-fed rotary printing press. In this device, dirt on the sheets isused for regulating the cleaning.

EP 0423093 A2 discloses a method and a device for cleaning guide rollersin a web-fed rotary printing press. Here, a web of material is wettedwith a cleaning agent. The guide rollers are braked for cleaning.

JP-A-01-031641 discloses a device for the cleaning of rollers in aweb-fed rotary printing press. Here, the web of material is additionallyprovided with a cleaning material and the start and end of the cleaningmaterial are detected by means of a sensor for controlling the cleaningprocess, for example the application of the cleaning material.

SUMMARY OF THE INVENTION

The present invention is based on the object of providing a method, aswell as a device for cleaning guide rollers.

This object is attained by the present invention by the provision of aweb of material that is provided with coded information, such as a barcode or a punch code. This information is read by a suitable sensor andis used to control the cleaning of the guide rollers in the web-fedrotary printing press.

The advantages which can be obtained by means of the present presentinvention lie, in particular, in that the guide rollers are cleaned inthe course of the passage of the paper web without it being necessary toperform a prior calculation of the path length between the guide rollersof the special paper web course and the storage of this distance in acomputer. No paper guide plans need to be prepared. In this way, thebraking of those guide rollers, which had not previously been wettedwith cleaning fluid, is also avoided, which otherwise could lead topaper web breaks.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the present invention is represented in thedrawings and will be described in greater detail in what follows. Shownare in:

FIG. 1, a schematic perspective representation of a device for theapplication of information and a device for the application of cleaningfluid to a web of material, and in

FIG. 2, a schematic perspective representation of a device acting on theguide roller for generating a speed difference, with a reading device inaccordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A web of material 1, for example a paper web 1, which is located betweena roll changer and print units of a web-fed rotary printing press, isguided in the production direction A over rotatable guide roller 2, 3,which are seated fixed in lateral frames, for example, as may be seen inFIG. 1. An output device 4 is arranged between the guide rollers 2, 3.This out put device 4 after it has received a control pulse, puts out areadable information, for example a two-track signal information 6, 7.This information, for example signal information 6, 7, can consist of apunched information, which is cut into the paper web 1 at distances “d”along the paper web 1 by a punch roller 11, which has punches 8, 9 onits circumference, wherein the punch roller 11 works against a punchreceiving roller 14, which has holes 12, 13 on the circumference.

These rollers 11, 14 can idle along, driven by friction, or can bedriven by a drive, not represented.

The punches 8, 9 of the punch roller 11 can be electrically extended,projecting past the circumference of the punch roller, 11 and can beretracted either individually or together, for example by means of atransmitter 16, which is connected via a line 17 with a control device18. This transmitter 16 transmits control commands and energy.

The information output device 4 can also apply information 6, 7 to theweb 1 of material by means of laser technology.

The information output device 4 in another embodiment, not specificallyrepresented, can also apply bar codes, for example by means of an inkjetprinting method.

Viewed in the production direction A, a device 19 for the application ofa cleaning agent 22 is arranged after or following the informationoutput device 4 and extends, for example in the form of a nozzle strip,transversely across the width of the paper web. The nozzle strip hasnozzles 21, which are placed next to each other and which apply thecleaning agent 22. The nozzles 21 are operated electromagnetically, forexample, and are connected with the control device 18 via lines 23.

Another form of a cleaning agent application device 19, not speciallyrepresented, for applying cleaning agent 22 can also consist of afountain roller located in a reservoir and having a doctor blade deviceand an application roller, which can be placed against the paper web 1.

Viewed in the production direction A, an information reading device 24is arranged before or ahead of the device 19 for the application of acleaning agent 22 and is connected via a line 26 with the control device18, all as may be seen in FIG. 1.

A device 28 for generating a speed difference between the guide rollers27 and the web 1 of material is assigned to a guide roller 27 or to agroup of guide rollers, as is depicted in FIG. 2.

This device 28 can consist of a friction brake, which acts on the guideroller 27, or respectively on its roller journal 29, and can beactuated, for example magnetically, pneumatically or hydraulically, bymeans of a control device 31 and via a line 32.

In place of a friction brake it is also possible to employ a drivemotor, not specially represented, acting on the roller journal 29, andwhich creates a difference between the circumferential speed of theguide roller 27 and the transport speed of the web 1 of material duringthe cleaning process.

Viewed in the production direction A, an information reading device 33is arranged ahead of the speed differential generating device 28 and isconnected via a line 34 with a control device 31. The control devices18, 31 are connected with each other by means of lines 36 and, ifrequired, are also connected with a central computer unit notspecifically depicted, as seen in FIG. 2.

In accordance with the invention, the process of cleaning the guiderollers 27 is performed as follows:

The cleaning process is started by a control command entered from acentral location, for example a central computer unit. The punches 8, 9of the punch roller 11 of the output device 4 are extended and cut atwo-track signal information 6, 7 into the paper web 1 at a spacing “b”,for example 150 mm. The signal information 6 is provided, for example,for putting the cleaning agent application device 19 into operation andfor applying cleaning agent, and the signal information 7, is providedfor example, for putting the device 28 for generating a speed differenceinto operation. The signal information 6, for example, determines theposition of the cleaning agent 22 on the web 1 of material. The nozzles21, which apply the cleaning agent 22 on the paper web 1, as seen inFIG. 1 are actuated by the first information reading cleaning deviceapplication device 24 of the device 19 for the application of thecleaning agent 22 as a function of the signal information 6. As soon asthe signal information 7 reaches second reading device 33 thereafter,the device 28 for generating a speed difference is switched on, and aspeed difference between the rotational speed of the surface of theguide roller 27 and the speed of travel of the web 1 of material iscreated, as depicted in FIG. 2. A maximum speed difference is forexample generated, i.e. the guide roller 27 is briefly braked to a stop.Thereafter, the release of the braking device takes place again. Thisstopping and starting of the guide rollers 27 can be repeated.

In the course of this, cleaning agent 22 is applied to the guide roller27 and is subsequently removed again; together with the ink remnants, bya section of the paper web 1 which is not wetted with cleaning agent.When the paper web 1 is no longer to be wetted, the signal information 6which is responsible for spraying is no longer issued.

Each guide roller 27 around and over which the paper web 1 “passes” iscleaned in this way.

The length of time the cleaning agent application device 19, as well asthe speed differential generating device 28, are switched on, can beextended after each switch-on pulse triggered by the signal information6, 7 by means of a time function element.

It is also possible to perform several sequential cleaning cycles.

In a second preferred embodiment, not specially represented, a sensor,for example the second information reading device 33, directlyinterrogates the cleaning agent 22 on the web 1 of material. This sensor33 can operate, for example, in accordance with capacitive, optical ormoisture-sensitive methods.

Thus, the position of the area of the web 1 of material wetted withcleaning agent 22 is detected by means of this sensor 33.

An output signal of this sensor 33 is used for the control of thecleaning process of the guide roller 27, or of a group of guide rollers.In particular, a speed difference between the rotating speed of thesurface of the guide roller 27 and the speed of travel of the web ofmaterial is generated as a function of the output signal of this sensor33.

The section of the web 1 of material used for cleaning preferably is apart of the material to be printed.

While preferred embodiments of a method and device for cleaning guiderollers in a web-fed rotary printing press in accordance with thepresent invention have been set forth fully and completely hereinabove,it will be apparent to one of skill in the art that a number of changesin, for example the specific roll changer structure, the particularweb-fed rotary printing press being used, and the like could be madewithout departing from the true spirit and scope of the presentinvention which is accordingly to be limited only by the followingclaims.

LIST OF REFERENCE NUMERALS

1 Paper web, web of material

2 Guide roller

3 Guide roller

4 Output device

5 -

6 Signal information, information

7 Signal information, information

8 Punch

9 Punch

10 -

11 Roller, first (8, 9)

12 Hole (14)

13 Hole (14)

14 Roller, second (12, 13)

15

16 Transmitter

17 Line

18 Control device

19 Device

20 -

21 Nozzle (19)

22 Cleaning agent

23 Line (21)

24 Reading device

25 -

26 Line (24)

27 Guide roller

28 Device

29 Roller journal (27)

30 -

31 Control device

32 line (28)

33 reading device (28), sensor

34 line (33)

35 -

36 line (18, 31)

A production direction (1)

B spacing (6, 6, 7, 7)

What is claimed is:
 1. A method for cleaning guide rollers in a web-fedprinting press including: providing a web of material to be printed in aweb-fed rotary printing press; applying information to said web ofmaterial in the form of one of a bar code and a punch code; providing acleaning agent application device before, in a production direction,guide rollers to be cleaned; providing a sensor for detecting saidinformation on said web of material; using said information on said webof material and detected by said sensor for operating said cleaningagent application device; applying cleaning agent to said web ofmaterial; passing said web of material over said guide rollers to becleaned; and cleaning said guide rollers during passage of said web ofmaterial carrying said cleaning agent over said guide rollers to becleaned.
 2. The method of claim 1 further including determining alocation of said cleaning agent on said web of material using saidinformation.
 3. The method of claim 1 further including providing adevice for causing a speed differential between said web of material andsaid guide rollers, and using said information for operating said devicefor causing a speed differential.
 4. The method of claim 3 furtherincluding providing a time function element and using said time functionelement, for controlling a length of time said device for causing aspeed differential is actuated.
 5. A device for cleaning guide rollersin a web-fed rotary printing press comprising: a web of material to beprinted in a web-fed rotary press; means for applying information in theform of one of a bar code and a punch code to said web of material; areading device for reading said information applied to said web ofmaterial; means for applying a cleaning agent to said web of material inresponse to said information applied to said web and read by saidreading device; and means directing said web of material with saidapplied cleaning agent past a guide roller to be cleaned.
 6. The deviceof claim 5 further including means for creating a speed differentialbetween said web of material and said guide roller, said means forcreating said speed differential being actuated by said reading device.7. The device of claim 6 wherein said means for creating said speeddifferential is a friction brake.
 8. The device of claim 6 wherein saidmeans for creating said speed differential is a motor brake.
 9. Thedevice of claim 5 wherein said means for applying said cleaning agentincludes a spray strip having spray nozzles, said spray strip extendingtransversely to a travel direction of said web of material.
 10. Thedevice of claim 5 wherein said means for applying said cleaning agentincludes a fountain roller located in a cleaning agent reservoir, adoctor blade in contact with said fountain roller, and an applicationroller in contact with said fountain roller and moveable into contactwith said web of material.